1. Field of the Invention
The present invention relates to a card connector for electrically and mechanically connecting a PC card to an electronic apparatus, such as a computer and, in particular, to an ejecting mechanism-equipped card connector for PC cards.
2. Brief Description of Prior Developments
Jpn. Pat. Appln. KOKAI Publication No. 8-96891 and U.S. Pat. Nos. 5,558,527 and 5,575,669 disclose an ejecting mechanism-equipped card connector in which even with the PC card mounted therein, a push button for the withdrawal of the PC card is retained in the same position as it is in a not-mounted state; and the push button is projected only when the PC card is withdrawn.
The ejecting mechanism basically includes an operation rod having a push button at an outer end section and spring-urged outwardly, a drive rod for driving a PC card withdrawal plate through a lever, an intermediate member driven under an action of a cam and allowing a connection or disconnection to be made between an outer operation rod and an inner drive rod, and a casing for slidably guiding the operation rod and the drive rod. A substantially heart-like cam groove is formed in the bottom wall of the casing with its projecting end side outward and the recessed side inward. When a cam follower pin projected from the operation rod engages with the cam groove and the operation rod is moved, it can be moved in the cam groove in a given direction. In a normal state, the cam follower is set in the recess of the heart-like cam groove, and the operation rod is retained against the urging force of the spring. As a result, the push button is not greatly projected outside the electronic apparatus, thus preventing an operation error of the push button and not interfering with other devices.
When the PC card is to be withdrawn, the push button is lightly pushed. By means of this action, the cam follower pin is pushed out of the recess of the heartlike cam groove. Thereafter, the cam follower pin is moved under the urging force of the spring along the groove toward the projecting end side, so that the push button is greatly projected toward an outside of the electronic apparatus. At this time, the intermediate member is driven under a cam action to allow a force to be transmitted from the operation rod to the drive rod. When the greatly outwardly projected push rod is pushed, an urging force acting on the push button is transmitted from the operation rod to the drive rod through the intermediate member, thus driving the lever and the PC card withdrawal plate. As a result, together with the movement of the PC card withdrawal plate, the PC card is also moved and withdrawn out of the card connector. When an urging force acting on the push button is released after the withdrawal of the PC card, the cam follower pin of the operation rod is again retained in the recess of the heart-like cam. The intermediate member, the drive rod and the PC card withdrawal plate are freely moved without interfering with the operation rod. In the case where an urging force acting on the push button is transmitted from the operation rod to the drive rod through the intermediate member so that the lever and the PC card withdrawal plate are driven, since the operation rod and the drive rod are guided along the inner surface of the casing, it is not folded at an abutting section to the intermediate member. However, the inner surface of the casing receives a force acting on the abutting section; for this reason, a biased unbalanced force is applied to the casing. Moreover, the conventional ejecting mechanism requires more components parts because the operation rod and the drive rod are contained in the casing and guided along the inner surface of the casing together with the intermediate member. Therefore, there is a growing demand for a card connector which can answer the recent tendency of the electronic apparatuses toward its miniaturization and high-performance functioning.